2023-2026 Hyundai Lamp Condensation TSB 25-BD-012H

Hyundai has released Technical Service Bulletin (TSB) 25-BD-012H to provide comprehensive information regarding condensation that may appear in the headlamps, rear combination lamps, daytime running lamps (DRL), or fog lamps across various 2023-2026 Hyundai models. This bulletin, which supersedes TSB 23-BD-002H, aims to clarify the causes of this condensation and outline appropriate diagnostic and repair procedures. For many cases of Hyundai Tucson lamp condensation, simply running the lamps with the engine on for a period can eliminate the moisture.

Symptoms

Owners may observe visible moisture or water droplets inside the lens of the headlamp, rear combination lamp, daytime running lamp (DRL), or fog lamp. This can range from light fogging to more noticeable water accumulation or streaks.

Causes of Lamp Condensation

The TSB identifies two primary causes for lamp condensation:

• Natural Condensation: This occurs due to temperature and humidity changes inside the lamp assembly. Factors like direct sunlight exposure, increased outside temperature, or the lamp assembly being cooled by rain or a car wash can cause moisture to condense on the inner lens surfaces. This type of condensation is considered normal, similar to windshield fogging, and typically does not require lamp replacement.
• Condensation from Engine Startup: Heat generated by the lamp bulbs and the engine can raise the temperature inside the lamp assembly. If the outer lens surface is simultaneously cooled (e.g., by washing the car or rain), moisture can condense on the inner lens. The amount and location of condensation can vary based on environmental factors and vehicle usage.

Important Warnings

• Lamp assembly replacement is NOT necessary in most cases for condensation. The condition can often be eliminated by turning on the lamps with the engine running for several minutes or during normal driving operation.
• For IONIQ vehicles, IONIQ repairs can only be performed at IONIQ certified dealers to avoid potential damage.
• If a lamp desiccant/moisture absorbent pack is replaced for a warranty claim, Do NOT use the lamp assembly for the replacement part; instead, file the claim with the desiccant/moisture absorbent pack as the replacement part and the lamp assembly as the causal part.
• Normal condensation is NOT REQUIRED to be replaced under warranty.
• If damage or modifications to the lamp assembly are caused by external influence, the Repair is NOT covered under warranty.
• Replace ONLY the lamp sub-assembly if it is available separately.

Diagnosis and Repair Procedure

The TSB outlines a flowchart to guide technicians through the diagnostic and repair process for Hyundai Tucson lamp condensation:

1. Initial Assessment: Determine if lamp condensation is present. If it's identified as normal condensation (e.g., after rain or a car wash, or in cold temperatures), proceed with the drying guidelines.
2. Drying Guidelines:
   • Park the vehicle in a well-ventilated area.
   • Remove any dust cap(s) from the lamp assembly (some may have two).
   • Turn the engine ON and switch the lamps ON to prevent battery discharge.
   • Allow the vehicle to idle for at least 30 minutes with the engine and lamps on to evaporate moisture.
   • Reinstall the dust cap(s).
3. Post-Drying Check: If condensation persists after following the drying guidelines, inspect for a potential water leak.
4. Water Leak Identification: Signs of a water leak include water collecting at the bottom of the lamp assembly, water streaks, or condensation remaining after the lamps have been on for 30 minutes or more. A water leak may be caused by a poor seal, cracks in the assembly, or poor fitment.
5. Further Inspection (if water leak suspected): Remove the lamp assembly and inspect for external damage or aftermarket modifications. If external damage or modifications are present, determine if they were caused by external influence. If so, the repair may not be covered under warranty.
6. Desiccant Replacement: If condensation remains after drying and no external damage or water leak is identified, or if it's determined to be an internal issue, replace the lamp desiccant or moisture absorbent pack (if equipped) and repeat the lamp assembly drying procedure.
7. Lamp Assembly Replacement: If all other steps fail to resolve the condensation, or if a severe water leak is confirmed not due to external influence, the affected lamp sub-assembly or entire lamp assembly may need replacement.

Required Parts

For cases requiring desiccant replacement, the following part is referenced:

• Desiccant/Moisture Absorbent Pack: Part Number 92125-*** (Note: The full part number needs to be ordered from the parts catalog for the specific model).

Source: NHTSA ID: 11025476